The head and torso of the Matroshka mannequin are made up of a total of 33 'slices'. At the core of the torso is a synthetic human skeleton, the 'bones' of which are embedded in moulded polyurethane plastic that simulates the varying densities of human body tissue.

Credit:
NASA.

MATROSHKA: a phantom on board the ISS Measuring space radiation and its effects

For the past 18 months, a phantom has been living on the outside of the International Space Station (ISS). Now, however, it’s keeping the ISS crew company. But we’re not talking about a peculiar kind of space ghost – our phantom is a scientific experiment called MATROSHKA for measuring the radiation level inside and outside the ISS. The ‘phantom’ is in fact a special dummy. The system for the experiment was developed and built by DLR.

By measuring the radiation dose received by astronauts both inside and outside the ISS, it is possible to gauge the risk posed by cosmic radiation to the human body. The findings from this experiment could help us develop countermeasures to provide suitable protection against cosmic radiation.

The ‘phantom dummy’, consisting of a head and upper body, looks rather like a human torso. Active and passive radiation detectors have been positioned at over 800 points inside the dummy, some of which are located in simulated human organs. These sensors have already provided us with valuable data which are now being analysed by a team of scientists. To simulate the protection provided by a spacesuit, during its stay on the outside of the ISS the dummy was encased in a carbon fibre container.

Koordinator: G. Reitz (DLR Köln)

Astronauts’ exposure to radiation - CHROMOSOME-2

When a human being spends extended periods in space, the rate of mutation of their chromosomes may be accelerated because of the level of radiation, resulting in an increased risk of cancer. Findings obtained so far from the astronauts and cosmonauts onboard the ISS have shown that long sojourns in space result in a significant increase in the rate of mutation, whereas short-term crews do not demonstrate any such change. Analysis of blood samples taken after the crews return to Earth indicates the presence of effective repair mechanisms, suggesting that the radiation risk for astronauts is acceptable.

Scientists at the University of Essen plan to use a new set of methods to study in more detail the mutagenic (mutation-causing) radiation exposure of ISS crew-members. The chromosomes of certain defence cells in the astronauts’ blood will be studied to see what changes occur. This method is already used on Earth to gauge the mutagenic effect of environmental toxins on humans